IUnit 8: physiology of human body system
Impact of lymphatic disorder and associated treatments
What is the lymphatic system:
Lymphatic system, a subsystem of the circulatory system in the vertebrate body that consists
of a complex network of vessels, tissues, and organs. The lymphatic system helps maintain
fluid balance in the body by collecting excess fluid and particulate matter from tissues and
depositing them in the bloodstream. It also helps defend the body against infection by
supplying disease-fighting cells called lymphocytes. This article focuses on the human
lymphatic system.
The fluid and proteins within the tissues begin their journey back to the bloodstream by
passing into tiny lymphatic capillaries that infuse almost every tissue of the body. Only a few
regions, including the epidermis of the skin, the mucous membrane, the bone marrow, and the
central nervous system, are free of lymphatic capillaries, whereas regions such as the lungs
gut , genitourinary system, and dermis of the skin are densely packed with these vessels.
Once within the lymphatic system, the extracellular fluid, which is now called lymph, drains
into larger vessels called the lymphatics. These vessels converge to form one of two large
vessels called lymphatic trunks, which are connected to veins at the base of the neck. One of
these trunks, the right lymphatic duct, drains the upper right portion of the body, returning
lymph to the bloodstream via the right subclavian vein. The other trunk, the thoracic duct,
drains the rest of the body into the left subclavian vein. Lymph is transported along the
system of vessels by muscle contractions, and valves prevent lymph from flowing backward.
The lymphatic vessels are punctuated at intervals by small masses of lymph tissue, called
lymph nodes, that remove foreign materials such as infectious microorganisms from the
lymph filtering through them.
Function of the lymphatic system
The lymphatic system has three functions:
1. The removal of excess fluids from body tissues. This process is crucial because water,
proteins, and other substances are continuously leaking out of tiny blood capillaries into the
surrounding body tissues. If the lymphatic system didn’t drain the excess fluid from the
tissues, the lymph fluid would build up in the body’s tissues, and they would swell.
2. Absorption of fatty acids and subsequent transport of fat, chyle, to the circulatory system.
, 3. Production of immune cells (such as lymphocytes, monocytes, and antibody producing
cells called plasma cells).
The role of the lymphatic system in the immunity :
The lymphatic system plays an integral role in the immune functions of the body. It is the first
line of defense against disease. This network of vessels and nodes transports and filters lymph
fluid containing antibodies and lymphocytes (good) and bacteria (bad). The body’s first contact
with these invaders signals the lymphatics, calling upon this system to orchestrate the way the
infection-fighting cells prevent illness and diseases from invading microorganisms. The spleen
also helps the body fight infection. The spleen contains lymphocytes and another kind of white
blood cell called macrophages, which engulf and destroy bacteria, dead tissue, and foreign matter
and remove them from the blood passing through the spleen.
Structure of the lymphatic system :
Impact of lymphatic disorder and associated treatments
What is the lymphatic system:
Lymphatic system, a subsystem of the circulatory system in the vertebrate body that consists
of a complex network of vessels, tissues, and organs. The lymphatic system helps maintain
fluid balance in the body by collecting excess fluid and particulate matter from tissues and
depositing them in the bloodstream. It also helps defend the body against infection by
supplying disease-fighting cells called lymphocytes. This article focuses on the human
lymphatic system.
The fluid and proteins within the tissues begin their journey back to the bloodstream by
passing into tiny lymphatic capillaries that infuse almost every tissue of the body. Only a few
regions, including the epidermis of the skin, the mucous membrane, the bone marrow, and the
central nervous system, are free of lymphatic capillaries, whereas regions such as the lungs
gut , genitourinary system, and dermis of the skin are densely packed with these vessels.
Once within the lymphatic system, the extracellular fluid, which is now called lymph, drains
into larger vessels called the lymphatics. These vessels converge to form one of two large
vessels called lymphatic trunks, which are connected to veins at the base of the neck. One of
these trunks, the right lymphatic duct, drains the upper right portion of the body, returning
lymph to the bloodstream via the right subclavian vein. The other trunk, the thoracic duct,
drains the rest of the body into the left subclavian vein. Lymph is transported along the
system of vessels by muscle contractions, and valves prevent lymph from flowing backward.
The lymphatic vessels are punctuated at intervals by small masses of lymph tissue, called
lymph nodes, that remove foreign materials such as infectious microorganisms from the
lymph filtering through them.
Function of the lymphatic system
The lymphatic system has three functions:
1. The removal of excess fluids from body tissues. This process is crucial because water,
proteins, and other substances are continuously leaking out of tiny blood capillaries into the
surrounding body tissues. If the lymphatic system didn’t drain the excess fluid from the
tissues, the lymph fluid would build up in the body’s tissues, and they would swell.
2. Absorption of fatty acids and subsequent transport of fat, chyle, to the circulatory system.
, 3. Production of immune cells (such as lymphocytes, monocytes, and antibody producing
cells called plasma cells).
The role of the lymphatic system in the immunity :
The lymphatic system plays an integral role in the immune functions of the body. It is the first
line of defense against disease. This network of vessels and nodes transports and filters lymph
fluid containing antibodies and lymphocytes (good) and bacteria (bad). The body’s first contact
with these invaders signals the lymphatics, calling upon this system to orchestrate the way the
infection-fighting cells prevent illness and diseases from invading microorganisms. The spleen
also helps the body fight infection. The spleen contains lymphocytes and another kind of white
blood cell called macrophages, which engulf and destroy bacteria, dead tissue, and foreign matter
and remove them from the blood passing through the spleen.
Structure of the lymphatic system :
